Failure to identify and treat a little-known spinal condition probably costs the NHS hundreds of millions a year, according to a leading consultant.
Cauda equina syndrome requires surgery within hours to avoid damage to the bowel, bladder, sexual organs and legs.
And it can be triggered by the most seemingly innocuous of body movements.
The Royal College of GPs says the condition is rare but every doctor should be on alert for it because of how serious it can be.
Red flag signs, include nerve pain down both legs as well as pins and needles or numbness around the bottom and inner thighs.
Catrina Farnell, of Skipton, Yorkshire, was 23 and a talented dancer with dreams of becoming a choreographer, when it happened to her.
She was in London, for an American football game, when she bent to pick up a bag.
"Something happened to my back," she says.
"It was excruciatingly painful. I didn't know what to do. I'd never even heard of cauda equina syndrome, so I didn't know there was a ticking clock above my head. I woke up a couple of hours later unable to move my legs, with numbness and pins and needles, and eventually unable to urinate."
Now 31 and reliant on crutches and a wheelchair, Catrina's legs, bowel, bladder and sexual organs are all severely damaged.
Her frail mother Margaret, 74, has become her carer.
Catrina says: "I want to have children and I want to meet someone to be with but it feels now that they'd be more of a carer, you know because being with me, people instinctively take on the role of looking after me.
"So, it just completely took that element of my life away."
'A matter of hours'
Cauda equina means "horse's tail" in Latin and describes the spray of nerves that come off the bottom of the spinal cord and activate the bladder, bowel, sexual organs and legs.
If a slipped disc hits these nerves, urgent medical treatment to remove the pressure is critical.
"Ideally you want to catch this condition in a matter of hours, do an MRI scan and do decompressive surgery," says John Reynard, a consultant urological surgeon at Oxford University Hospitals NHS Trust.
But there is a widespread belief that a shortage of resources and a lack of awareness among medical professionals is exacerbating the problem.
"CES requires a clinical and radiological diagnosis, so it is critical that patients get an MRI scan, which is the only way to confirm the condition," says Nisaharan Srikandarajah, a trainee neurosurgeon with a PhD in cauda equina syndrome.
"Sadly there is a shortage of MRI radiographers working out of hours, which causes delays in getting the critical diagnosis."
After 24 hours, the damage to the cauda equina is such that outcomes for patients become significantly worse.
Martin Brown, a former champion weightlifter, injured his cauda equina in the gym.
"They don't see me at home crying every night, or struggling trying to get the energy to get up, put my brave face on and pretend that everything's all right," he says.
"My masculinity went with having trouble with sexual dysfunction.
"I still have to have a strict regime to manage my bowels, my bladder.
"It's demoralising and dehumanising. It really knocked my self-confidence."
Catrina and Martin are supported by the Cauda Equina Syndrome Association, set up by Claire Thornber, who also has the condition, and based at Broughton Hall, in Skipton, where it offers emotional and psychological rehabilitation.
Assessing how many people have the condition is difficult as some hospitals do not log case numbers.
However, the last NHS figures available, for 2010-11, show 981 surgical decompressions for CES in England alone.
These figures do not include claims against GPs - and John Reynard believes the true cost is far higher.
"It's difficult to get a precise figure from all the various information sources about the frequency of delays in diagnosis of cauda equina syndrome," he says.
"I would estimate that it is something in the order of £150m to £200m a year in terms of compensation payments, covering legal costs."
Prof Helen Stokes-Lampard, chairwoman of the Royal College of GPs, compared the condition to meningitis.
"Cauda equina syndrome is a rare condition but, like meningitis, one that every doctor will be on alert for because of how serious it can be if not detected and managed swiftly," she said.
"The vast majority of acute back pain and back problems will not be serious and can be safely managed through careful exercises or over-the-counter painkillers, but if a patient experiences any of the red-flag symptoms for cauda equina syndrome, they should seek medical attention as soon as they can."
Specialist lawyers have little doubt that medical professionals too often act too slowly or fail to recognise the key signs of the syndrome.
Sally Leonards, a partner at JMW Solicitors, said: "My concern as a lawyer, having done this work for over 20 years, is that I'm still seeing the same cases coming through. I'm still seeing the same themes arising and the NHS don't seem to be learning from the mistakes."
Compensation payments can reach £4m, excluding legal fees.
They are high partly because many of those who get cauda equina syndrome are young, may not be able to work again and need lifetime care.
NHS Resolution, formerly the NHS Litigation Authority, said it was "committed to sharing information with our NHS trust members to highlight some of the red flags related to cauda equina syndrome".
"We are working closely with trusts and the wider NHS system to reduce avoidable harm to patients," it said.